soc/intel/quark: Add I2C support
Add the I2C driver.
TEST=Build and run on Galileo Gen2
Change-Id: I53fdac93667a8ffb2c2c8f394334de2dece63d66
Signed-off-by: Lee Leahy <leroy.p.leahy@intel.com>
Reviewed-on: https://review.coreboot.org/14828
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
diff --git a/src/soc/intel/quark/gpio_i2c.c b/src/soc/intel/quark/gpio_i2c.c
new file mode 100644
index 0000000..d23a905
--- /dev/null
+++ b/src/soc/intel/quark/gpio_i2c.c
@@ -0,0 +1,195 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2016 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <console/console.h>
+#include <delay.h>
+#include <device/device.h>
+#include <device/i2c.h>
+#include <device/pci.h>
+#include <device/pci_ids.h>
+#include <soc/i2c.h>
+#include <soc/ramstage.h>
+#include <soc/reg_access.h>
+
+static void i2c_disable(I2C_REGS *regs)
+{
+ uint32_t status;
+ uint32_t timeout;
+
+ /* Disable I2C controller */
+ regs->ic_enable = 0;
+
+ /* Wait for the enable bit to clear */
+ timeout = 1 * 1000 * 1000;
+ status = regs->ic_enable_status;
+ while (status & IC_ENABLE_CONTROLLER) {
+ udelay(1);
+ if (--timeout == 0)
+ die("ERROR - I2C failed to disable!\n");
+ status = regs->ic_enable_status;
+ }
+
+ /* Clear any pending interrupts */
+ status = regs->ic_clr_intr;
+}
+
+int platform_i2c_transfer(unsigned bus, struct i2c_seg *segments, int count)
+{
+ uint8_t *buffer;
+ int bytes_transferred;
+ uint8_t chip;
+ uint32_t cmd;
+ int length;
+ int read_length;
+ I2C_REGS *regs;
+ uint32_t status;
+ uint32_t timeout;
+
+ regs = get_i2c_address();
+
+ /* Disable the I2C controller to get access to the registers */
+ i2c_disable(regs);
+
+ /* Set the slave address */
+ ASSERT (count > 0);
+ ASSERT (segments != NULL);
+ ASSERT (segments->read == 0);
+
+ /* Clear the start and stop detection */
+ status = regs->ic_clr_start_det;
+ status = regs->ic_clr_stop_det;
+
+ /* Set addressing mode to 7-bit and fast mode */
+ cmd = regs->ic_con;
+ cmd &= ~(IC_CON_10B | IC_CON_SPEED);
+ cmd |= IC_CON_RESTART_EN | IC_CON_7B | IC_CON_SPEED_100_KHz
+ | IC_CON_MASTER_MODE;
+ regs->ic_con = cmd;
+
+ /* Set the target chip address */
+ chip = segments->chip;
+ regs->ic_tar = chip;
+
+ /* Enable the I2C controller */
+ regs->ic_enable = IC_ENABLE_CONTROLLER;
+
+ /* Clear the interrupts */
+ status = regs->ic_clr_rx_under;
+ status = regs->ic_clr_rx_over;
+ status = regs->ic_clr_tx_over;
+ status = regs->ic_clr_tx_abrt;
+
+ /* Process each of the segments */
+ bytes_transferred = 0;
+ read_length = 0;
+ buffer = NULL;
+ while (count-- > 0) {
+ buffer = segments->buf;
+ length = segments->len;
+ ASSERT (buffer != NULL);
+ ASSERT (length >= 1);
+ ASSERT (segments->chip = chip);
+
+ if (segments->read) {
+ /* Place read commands into the FIFO */
+ read_length = length;
+ while (length > 0) {
+ /* Send stop bit after last byte */
+ cmd = IC_DATA_CMD_READ;
+ if ((count == 0) && (length == 1))
+ cmd |= IC_DATA_CMD_STOP;
+
+ /* Place read command in transmit FIFO */
+ regs->ic_data_cmd = cmd;
+ length--;
+ }
+ } else {
+ /* Write the data into the FIFO */
+ while (length > 0) {
+ /* End of the transaction? */
+ cmd = IC_DATA_CMD_WRITE | *buffer++;
+ if ((count == 0) && (length == 1))
+ cmd |= IC_DATA_CMD_STOP;
+
+ /* Place a data byte into the FIFO */
+ regs->ic_data_cmd = cmd;
+ length--;
+ bytes_transferred++;
+ }
+ }
+ segments++;
+ }
+
+ /* Wait for the end of the transaction */
+ timeout = 1 * 1000 * 1000;
+ do {
+ status = regs->ic_raw_intr_stat;
+ if (status & IC_INTR_STOP_DET)
+ break;
+ if ((status & (IC_INTR_RX_OVER | IC_INTR_RX_UNDER
+ | IC_INTR_TX_ABRT | IC_INTR_TX_OVER))
+ || (timeout == 0)) {
+ if (timeout == 0)
+ printk (BIOS_ERR,
+ "ERROR - I2C stop bit not received!\n");
+ if (status & IC_INTR_RX_OVER)
+ printk (BIOS_ERR,
+ "ERROR - I2C receive overrun!\n");
+ if (status & IC_INTR_RX_UNDER)
+ printk (BIOS_ERR,
+ "ERROR - I2C receive underrun!\n");
+ if (status & IC_INTR_TX_ABRT)
+ printk (BIOS_ERR,
+ "ERROR - I2C transmit abort!\n");
+ if (status & IC_INTR_TX_OVER)
+ printk (BIOS_ERR,
+ "ERROR - I2C transmit overrun!\n");
+ i2c_disable(regs);
+ return -1;
+ }
+ timeout--;
+ udelay(1);
+ } while(1);
+
+ /* Finish reading the data bytes */
+ while (read_length > 0) {
+ status = regs->ic_status;
+ *buffer++ = (UINT8)regs->ic_data_cmd;
+ read_length--;
+ bytes_transferred++;
+ status = regs->ic_status;
+ }
+
+ return bytes_transferred;
+}
+
+__attribute__((weak)) void mainboard_gpio_i2c_init(device_t dev)
+{
+ /* Initialize any of the GPIOs or I2C devices */
+ printk(BIOS_SPEW, "WEAK; mainboard_gpio_i2c_init\n");
+}
+
+static struct device_operations device_ops = {
+ .read_resources = pci_dev_read_resources,
+ .set_resources = pci_dev_set_resources,
+ .enable_resources = pci_dev_enable_resources,
+ .init = mainboard_gpio_i2c_init,
+};
+
+static const struct pci_driver gfx_driver __pci_driver = {
+ .ops = &device_ops,
+ .vendor = PCI_VENDOR_ID_INTEL,
+ .device = I2CGPIO_DEVID,
+};